Issue with Collection:ofType

I want to use collection with choosen template only and i want to paginate it.
I try to use ofType method, but my collection looks strange - like an array which contains empty value or something similar.


.md file header

title: Home
page@.descendants: /notes
exclude: topic
limit: 3
by: date
dir: desc
pagination: true

Folder structure:

And part of template code:

{% set collection = page.collection.ofType('note') %}
        {% for child in collection %}
                {% set image =['_header.jpg'] %}
                {% set image = image ? image :|randomize|first %}

                {% include 'partials/preview.html.twig'  with {'child': child, 'image':image} %}
                {% if not loop.last %}
                        <hr class="note-hr"/>
                {% endif %}
        {% endfor %}

        {% if config.plugins.pagination.enabled and collection.params.pagination %}
            <div class="pure-g">
                <div class="pure-u-1 text-center">
                    {% include 'partials/pagination.html.twig' with {'base_url':page.url, 'pagination':collection.params.pagination} %}
        {% endif %}

I thought this collection should contains only 4 elements, and i expected to got only 2 pages with 3 and 1 item
But i get - 3 pages and first page empty and others contains 2 items each:
page 1
page 2
page 3

Ok, i think i understood what happens and i try to clarify my questions - there is a method to paginate a filtered collection?
Because pagination plugin continues to use page.collection() for pagination